Hyperthyroidism

Hyperthyroidism: Overview

The leading cause of hyperthyroidism (also known as thyrotoxicosis or 'overactive thyroid') is Graves' disease. Graves' disease represents a basic defect in the immune system, causing production of immunoglobulins (antibodies) which stimulate and attack the thyroid gland, causing growth of the gland and overproduction of thyroid hormone. Similar antibodies may also attack the tissues in the eye muscles and in the skin on the front of the lower leg.
Some facts:

Graves' disease occurs in less that 1/4 of 1% of the population, but as many as 3% to 4% of asymptomatic populations have been found to have suppressed TSH levels suggestive of subclinical Graves' disease.

Graves' disease is more prevalent among females than males.

Graves' disease usually occurs in middle age, but also occurs in children and adolescents.

Graves' disease is not curable, but it is a very treatable disease.

The thyroid gland is shaped like the letter "U." The larger side parts are tucked in behind neck muscles next to the trachea (windpipe) while the middle connecting part is closer to the skin, just below the larynx (Adam's apple). It is like two walnuts connected at the bottom by an almond. The normal gland is barely palpable by a physician's hand, and then it is only the connecting part that can be felt. Enlargement of the gland occurs with most thyroid ailments and is either generalized (a goiter), nodular (bumpy) or both.

The sole function of the thyroid gland is to make thyroid hormone. The production process involves uptake of iodine from the bloodstream and attachment of this mineral to a protein produced within the gland. Production and release of thyroid hormone by the thyroid gland are controlled by another gland – the pituitary. Living at the base of the brain, the pituitary gland senses the body's need for thyroid hormone and then triggers the thyroid gland by releasing a chemical named thyroid stimulating hormone, or TSH. As you might guess, disease of the pituitary can affect function of the thyroid gland.

Thyroid hormone is the body's "governor." It controls the rate of metabolism – the speed of physiologic processes and functions. Normally everything is fine-tuned. The thyroid and its pituitary controller keep the body's machinery running at the most effective and efficient rate. But a host of environmental and genetic factors can foul the system.

The most common disease of the thyroid gland is hypothyroidism, or under function. With too little thyroid hormone, the machinery slows and the person slows. Fatigue, somnolence, mental sluggishness, and a desire for high room temperature are common symptoms. In advanced states the victim has thickened and boggy facial skin, a slow raspy voice, baggy eyes and a dull appearance. Thinking is slowed, and the person may appear depressed or even confused. Because an underactive thyroid gland develops slowly, the problem often goes unrecognized by the patient, the family and even the physician. Too often the trouble is attributed to old age. Diagnosis is easy if a blood test is obtained. And treatment with a daily thyroid hormone tablet is also easy.

Over function of the thyroid gland is less common than under function, but is not uncommon in the elderly.

Incidence; Causes and Development

Although Graves' disease most frequently occurs in women in their middle decades (8 times more than men), it also occurs in children and in the elderly.

There are several elements contributing to the development of Graves' disease. There is a genetic predisposition to autoimmune disorders and infections and stress play a part. Graves' disease may have its onset after an external stressor In other instances, it may follow a viral infection or pregnancy. Many times the exact cause of Graves' disease is simply not known. It is not contagious, although it has been known to occur coincidentally between husbands and wives.

The metabolic speed-up associated with hyperthyroidism is easily diagnosed in younger patients who present with symptoms of weight loss, excess appetite, sweating, rapid pulse and tremor. In older adults these characteristic symptoms may not exist. The elderly often present with depressed mood, confusion, heart failure, irregular pulse rate and a myriad of symptoms that do not readily suggest an acceleration of metabolism.

Diagnosis and Tests

Advances in laboratory technology now allow both underactive and overactive thyroid conditions to be diagnosed quickly and accurately with simple blood tests. Geriatricians routinely examine a patient's thyroid gland and order periodic blood checks – they believe it is best to detect and treat thyroid problems before significant symptoms arise. It is another reason why regular medical checkups are important for older adults.

Treatment and Prevention

Once diagnosed, treatment of hyperthyroidism in an older person is safely accomplished by administration of radioactive iodine. The zapped iodine molecules are taken up by the thyroid gland and tame the overactive factory.

The selection of treatment will include factors such as age, degree of illness, and personal preferences. Generally speaking, from least invasive to most invasive, the treatments include:

Anti-thyroid drugs that inhibit production or conversion of the active thyroid hormone (20-30% effective, often used to control mild cases)

Radioactive iodine (I-131), which destroys part or all of the thyroid gland and renders it incapable of overproducing thyroid hormone

Surgery, in which most of the thyroid gland is removed, renders it incapable of overproducing thyroid hormone.

The latter two treatments result in a 90-95% remission rate of the disease. In a few cases the treatments must be repeated. In all cases lifetime follow-up laboratory studies must be done, and in almost all cases lifetime replacement thyroid hormone must be taken.

Prognosis; Complications

Grave's disease usually responds to treatment and, after the initial period of hyperthyroidism, is relatively easy to treat and manage.

Another common disorder of the thyroid gland is a nodule, or lump. A physician's main concern is whether the growth is caused by cancer. Fortunately, the vast majority of nodules discovered in the elderly are harmless. "Wait and watch" is usually the best advice. If cancer of the gland is discovered, the prognosis with treatment is usually good.

The more serious complications of prolonged, untreated, or improperly treated Grave's disease include weakened heart muscle leading to heart failure, osteoporosis, or possible severe emotional disorders.

Skin-Hair-Nails

Symptoms - Glandular

Risk factors for Hyperthyroidism:

Addictions

A study of 132 pairs of twins (264 subjects) showed that smoking can have negative effects on the endocrine system, causing a 3- to 5-fold increase in the risk of all types of thyroid disease. The association was most pronounced in autoimmune disorders (Graves' disease and autoimmune thyroiditis), although there was still a strong association for non-autoimmune thyroid disorders.

Family History

Nutrients

Although supportive data is limited, a report from a study group of hyperthyroid women suggests that copper status should at least be investigated in women with hyperthyroidism.

"Thyroid and immune system health are crucially dependent upon copper. As far as I can see now, copper deficiency is the most important factor in the development of hyperthyroidism. Virtually all hypers in the hyperthyroidism group have found that copper supplementation reduced their symptoms, usually within hours or a few days at most. Most have reported that within three to six months of beginning copper supplementation, they have been able to significantly reduce their intake of antithyroid drugs. While copper is the big story in hyperthyroidism, it is not the whole story. If it were, it would have been discovered years ago. Proper copper metabolism interrelates with and depends upon many other nutrients." [John Johnson, iThyroid.com]

Hyperthyroidism suggests the following may be present:

Addictions

A study of 132 pairs of twins (264 subjects) showed that smoking can have negative effects on the endocrine system, causing a 3- to 5-fold increase in the risk of all types of thyroid disease. The association was most pronounced in autoimmune disorders (Graves' disease and autoimmune thyroiditis), although there was still a strong association for non-autoimmune thyroid disorders.

One doctor reports that taking calcium without magnesium is one of the worst things you can do if you have hyperthyroidism because this increases any magnesium deficiency and increases the heart rate and likelihood of arrhythmia. This is one of the reasons why dairy products, which are high in calcium and low in magnesium, need to be restricted until magnesium levels are replenished.

Mineral

Very high doses of Iodine for short periods (about thirty drops daily of SSKI for three weeks) have sometimes produced favorable results in Graves' disease. Because of the possibility of causing a 'thyroid storm' (an acute hyperthyroid state), this therapy should only be attempted under close supervision by a doctor experienced in its use: Excessive iodine ingestion can cause either hypothyroidism or hyperthyroidism and should be avoided.

On June 22, 2001 Dr. Barbara Gasnier reported the findings at the 83rd Annual Meeting of the Endocrine Society in Denver, Colorado that selenium supplementation may prevent progression of autoimmunethyroid disease, especially during the onset of the disease.

According to the researchers, selenium deficiency appears to contribute to the development and maintenance of autoimmune thyroiditis because of its effect on the function of selenium-dependent enzymes, which can modulate the immune system.

Selenium supplementation with 200mcg of sodium selenite may improve the inflammatory activity seen in patients with autoimmune thyroiditis, but whether this effect is specific for autoimmune thyroiditis or may also be effective in other organ-specific autoimmune diseases remains to be investigated. Selenium supplementation may lower free radical activity, which contributes to inflammation.

It appears that taking selenium without iodine will result in a decrease in production of Thyroxine (T4), although there may be an initial transient increase in T4 to T3 conversion and hence higher T3 and seemingly worse hyperthyroidism.